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| |
| # Druid's Code Coverage Enforcement |
| |
| Druid code repository has an automated way of checking if new code has enough code coverage. |
| Druid CI checks are configured to enforce code coverage using JaCoCo. The CI checks will prevent a PR from being merged |
| if test coverage of new added code is below the set threshold. The CI checks filters test coverage based on a diff from |
| your PR and make sure that the thresholds are met. Druid currently enforce branch and line code coverage. |
| |
| However, do note that our current code coverage checks are merely smoke tests. They only verify that a line or branch |
| of code has been called during the test, but not that the functionality has been tested sufficiently. |
| Reviewers should still verify that all the different branches are sufficiently tested by reviewing the tests. |
| |
| ## Running code coverage locally |
| Code coverage should be run locally to make sure the PR will pass Druid CI checks. |
| 1. Code coverage on the codebase can be generated directly in [Intellij](../intellij-setup.md#Set-Code-Coverage-Runner). |
| 2. Code coverage on just the diff of your PR can be generated in your terminal. First, you will have to install |
| diff-test-coverage by running `npm install @connectis/diff-test-coverage`. Next, run the unit tests |
| for the module you are working on `mvn -pl <MODULE_TO_CHECK> test jacoco:report` |
| (this will create a HTML report in target/site/jacoco/index.html). Finally, run |
| `git diff master...HEAD | diff-test-coverage --coverage "**/target/site/jacoco/jacoco.xml" --type jacoco --log-template "full" --` |
